Prusa i3 MK3 Upgrade

My team is looking into buying a 3D printer and we’re debating between the Prusa and Onyx One. Just curious if the upgrade for the Prusa is worth the $300 price tag. Thanks!

Prusa i3 MK3 is $1000 + shipping
The Onyx One is $3500 + shipping

If your team has the money to buy a Markforged I would absolutely recommend them as they are amazing printers that can print parts plenty strong enough for an FRC robot.
However, the price is prohibitive for a lot of teams and a Prusa i3 MK3 will be more than enough to get your team into 3d printing parts.
I personally have an i3 MK2s and it has served me very well over the last year, but if you have the money for a Markforged, do it. They are awesome and ONYX filament is some of the best stuff you can get

^ Be careful with the Markforged machines; even if you can afford or convince your school to purchase the machine itself, consumables ~8x as expensive as standard PETG or ABS filament might become a problem (even polycarb is just ~$40 a kilo). With the Onyx One, you’re paying more for a solid machine and customer support rather than the unique features of the Onyx 2 and Pro machines. Just something to consider.

personally, I would go with the mark 3. user base is great.

Although the cr10 is also an option…

properly tuned, it can provide some great prints.

I’ve been running an Onyx One at work almost non-stop for the last few weeks, but have never used a Prusa printer of any kind. I really can’t speak for the long term reliability of the Onyx One.

That said, I’d strongly consider that Markforged is located in Massachusetts, while Prusa headquarters is in Prague. I recently had some replacement parts shipped over for the Onyx One*, which I received in 2 business days. It’s possible that replacement part shipments would be even faster for you. A colleague has had issues in the past with regards to replacement part lead times from Prusa HQ. Yes, you can get a lot of replacement Prusa parts online from US retailers, but I feel that somewhat defeats the purpose of getting the printer directly from Prusa.

If at the end of the day your budget doesn’t allow for a $3500 printer or you decide that some sort of Prusa i3 is right for your, I’d strongly consider the Prusa-based Pulse series by Matterhackers, who are located in Southern California. The range starts at $800 and goes up to a $1600 for the Pulse XE, which 3847 seems to have had great success with. You can think of the XE as an Onyx One competitor, as it was designed to print MatterHacker’s NylonX chopped carbon filament.

Troy brings up a good point regarding filament price. Although, if your are comparing the Pulse XE w/ NylonX to the Onyx One, the cost difference is more like ~2x (~$200/kg of Onyx vs ~115-120/kg of NylonX). On the other hand, the Pulse XE is capable of printing much less expensive filaments.

*The machine shipped with a bad bearing on one of the idler pulleys. It was still running regardless and making great parts, but I couldn’t afford to have the machine down.

One of our FTC teams recently purchased an Ender3. and have to admit it is a nice printer for 225$. Check Amazon. After the students get up to speed, we will do some upgrades. E3DV6 clone with a hardened nozzle, add bed height sensor, Flash Marlin to latest version with bed leveling, and some other little parts. Still under 300$. If team needs larger bed CR10 isn’t bad either with similar mods.

The FRC team has been printing some prototype parts that are larger than the Markforge Onyx one bed. We use 3DXTECH Carbonx nylon CF and the parts match or exceed onyx filament. You don’t have to spend 3000$ to print structural parts. However, the learning curve and knowledge to acquire are significant. Markforge is more plug and play. Filament is very expensive.
I prefer to test in cheap PLA+ and then go to PETG or the carbon filaments for production parts. This is not an option with Markforge.

The prusa with a hardened nozzle is a very capable printer.

I have both a Prusa Mk3 and a Rep Rap (DIY from scratch) printer. The Prusa is amazing and works for everything I give it. It does exotic materials as well. I would advise against the cheap 3d printers as they are not as reliable and Marlin is touchy. I think that the expensive ones such as the Onyx are fine, but do consider that the Prusa has excellent support and forums and it accepts 1.75 (thus I can give it many materials including carbon fiber) which allows for more versatility and cheaper operation (because 90% of what you are doing will not require carbon fiber). I do think that the Prusa is equal to the Onyx. Also a team can build the printer with the Prusa which is fun.

This is a pretty important point (and a question that Markforged was unwilling to answer over email). Are the Onyx printers not able to print other filaments as easily? I found some forums with people saying that printing PLA or ABS will reduce the quality of your prints permanently.

When choosing a 3D printer you have to consider what is the purpose of the printer. Is it to prototype with multiple materials or are you trying to create usable parts. A Marked Forged is an amazing printer that if tuned properly from the start will create great parts using Onyx material. This is very limiting considering the price if you are doing rapid prototyping and need to iterate multiple times. I use an Onyx one for my carbon fiber stuff but it is dedicated to things that have already been tested or require little iteration. I do not have a Pursa in my shop but we do have one at home that my daughter uses. These things are amazing for multiple materials. But you do have to be good with tweaking your slicer settings unlike the marked forge which has defaults that work perfectly with their material. But if you want to spend 4000 on a versatile printer consider a Raised 3D that is my go to for multiple materials in my shop.

If you own a Prusa or a clone then do yourself a favor and get a license for Simplify3D. They offer a discount for students/educators and it’s well worth it over the other slicers. I can’t recommend it enough.

The price of Prusa i3 ‘MK2’ (it’s not quite a build match) have come way, way down.
I’ve seen workable kits for as low as $250.

I’ve been building RepRap printers for a long time - I was able to get a kit for $289 with shipping a little over a year ago and it was basically a complete set of parts for a single extruder printer with SD card reader and LCD display.

As I recall that kit even included some cheap acme screws. I don’t have the printer at the moment.

Course you’ll now have to assemble and calibrate it, but it’s doable.

I was printing with MicroCenter Inland PLA/ABS in that printer (I have a list of PLA compatible with the extruder settings I use).

Here’s a newer dual extruder version of the ANet printer I am describing:


Please note that the design for a Prusa printer is opensource.
But there is Prusa Research:

Very very good point about the difference between an Original Prusa i3 and a generic Prusa i3.

Personally, I can highly recommend an Original Prusa i3 Mk3. I did nine days of prints in about 12 days in early September and had only one failed print. They are truly remarkably reliable machines. The generic Prusa i3 market is extremely variable, and the printer is likely to be as much of a project as anything you want to make on it in the sub-$400 range. Certainly you can get good prints out of them, but it’s a balance of how much time you’re willing to spend on the printer itself versus making parts on it.

I have been building RepRap printers since before it was really a thing.

The tough bits for a build by someone without experience to assemble an opensource Prusa I3:

  1. Making sure you have a complete set of parts meant to work together. Buying a kit addresses that.

  2. Understanding how it all works together, buying a kit won’t help with this. Don’t follow directions and you’ll find out the hard way. As you would with most FRC robots.

  3. Calibration can be tricky if you are more mechanically inclined than software inclined. However you can get bit here with a fully assembled printer as it wears or if it gets banged around in shipping.

  4. Getting extruder settings right can be a lot of trial and error. Hence why I print with specific part numbers of material I can get in many colors easily. It took a bunch of effort to get these parameters. Each new material can restart the trial and error.

On the flip side. An open source printer can be real cheap. Therefore easier to get more as it’s a slow printing process. The parts are more generic. You are never locked into a vendor or process. No one invalidates your warranty because they have some arbitrary gripe. Shipping someone a box of parts is much less an issue if it gets thrown down the walkway to your porch than if they do that with your assembled printer (yes FEDEX was ‘helping’).

I personally have a prusa i3 mk2 and it works beautifully. Most maintenance I’ve done is tightening some bolts, or updating firmware. The parts are beautiful, it holds up amazingly, and it doesn’t cost as much as its competitors. My school has a couple lulzbot printers for engineering classes, and I still prefer my prusa for ease.

Go for the Prusa i3 Mk3. In our team, 3 of the mentors own a Mk3, two of which were bought as kits and mine, which I bought pre-assembled.

The Prusa is a workhorse. Mine has been running almost 24/7 since the beginning of July. I love the diversity of filament the i3 can handle. i have printed so far with PLA, Flexible PLA, PETG, ABS and Cabon Fiber reinforced Nylon, the latter to print some of the parts for a fascinating FRC robot project. The i3 also offers a larger print volume than that of the Onyx One.

Last, but not least, the Prusa i3 Mk3 is an Open Source project, so if your team favours that approach in how the team operates, this printer is definitely the one for you.

Huh haven’t heard of the Pulse XE and looking at it, it seems to better than the Prusa. Also, I found out that I will probably $2k to spend on only a 3D printer so should I just roll with Pulse or any other options? (no Onyx One :frowning: )

I personally have a Prusa i3 MK2.5 (had a Mk2S for a year and a half, just upgraded). I couldn’t recommend Prusa enough. Their customer service, quality, attention to detail, and constant updates make it one of the most reliable and “state of the art” (ok, state of the art for DIYers) printers on the amateur market. If you have $2k to spend, I would personally order two Prusa’s (Mk2S or Mk3), or one printer (MK3) and the MMU2 kit (development on it has been very promising). I’ve been able to print everything from PLA, ABS, PETG, Nylon, CF filled, and more (with a ruby nozzle), and the quality is better than printers worth 5x more.

Overall, order for your needs, but you could never go wrong with a Prusa.

Some teams have a sufficient budget to spend $5000 on 3D printing instead of $1500. They are spending the money so they can spend more time on CAD and robot design. This is valid if they have the money to do it and want to spend it in that way. For our team, funding is enough of a constraint at this time that we would not choose to spend the extra on MarkForged. If we ever have 2-3 Prusa’s (or equivalent) already and want to add more capacity, and we have the budget, that’s when we’d potentially be open to adding a more expensive printer.

We have an old Stratasys that used to be our only 3D printer, and the filament for that machine used to cost $260/kg. It was frustrating and limiting when the cost of consumable materials was high enough to affect my willingness to print whatever idea a student comes up with or print lots of versions of things. With cheap filament, we print whatever we want and life is good. But, getting the printers working and figuring out how to use them consumes time.

a thread on how to get good results with a main stream printer and filaments like nylon-x would be great!

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